1. Field of the Invention
The present invention relates to a hard disk drive, and more particularly to a covering device of a hard disk drive, which is assembled to a base of the hard disk drive.
2. Description of the Related Art
Generally, a hard disk drive performing a function of an auxiliary memory is regarded as an important element of a computer. High capacity of a hard disk drive through high density recording is considered as an unavoidable factor in a multimedia environment of modem times. According to this, there is keen competition in the art of a hard disk drive, to occupy high ground where the situation of high capacity can be met by producing a new head and media through more innovative technical development.
A hard disk drive is a precise mechatronics product which has electronic parts and mechanical parts. The hard disk drive being used as one of auxiliary memories serves to record and reproduce information to and from a disk having magnetic susceptibility by transmitting a digital signal to a head which functions as an electromagnet.
However, the cover of the hard disk drive of the related art suffers from defects in that since the cover of the hard disk drive is manufactured by aluminum die casting, dimensional precision is deteriorated, and a post-process for removing a burr created when the cover is die-casted is additionally needed.
Further, since the separate coating must be applied to the cover after the aluminum die casting is completed, a high grade cleansing procedure has to be provided, which in turn increases manufacturing cost.
Also, the cover manufactured by die casting aluminum or press working a aluminum plate amplifies the vibration transferred thereto from the rotating shaft of the spindle motor and/or the pivot shaft of the actuator, thereby to boost vibration transmissibility. To overcome this problem, although a damper is used between the cover and the rotating shaft and/or the pivot shaft, since bond is used, outgasing is caused and manufacturing cost is increased.
In addition, even in the case that the cover is made of plastic according to the related art, vibration and noise generated when the spindle motor is rotated and the actuator is pivoted, are not sufficiently dampened, and rigidity thereof is reduced. Furthermore, since the cover is locked to the base by screws made of stainless steel, plastic particles are created and flowed into the hard disk drive when the screws are passed through locking holes defined in the cover. This creation of plastic particles and the inflow thereof into the hard disk drive severely diminishes reliability of the hard disk drive.
U.S. Pat. No. 5,483,397 for a Damping Configuration For Improved Disk Drive Performance to Gifford et al discloses a viscoelastic damper positioned within a hard disk drive enclosure in contact with the top cover of the disk enclosure and the top of the spindle shaft. However, the damper forms the shape of a solid washer. I have not seen the use of slits in a washer or a damper to more effectively reduce the noise and vibrations created during use of a hard disk drive. Also, I have not seen a damper for the pivot shaft of the actuator that is in the shape of the operating area of the actuator.